1. Technical Field
The present invention relates to a gearshift unit of a so-called shift-by-wire type for motor vehicle. The gearshift unit, according to the invention, is primarily intended for use in a driver's cab of a truck, but can be advantageously used in other types of vehicle such as conventional passenger cars, so-called minivans, multi-purpose vehicles (MPVs) and sport-utility vehicles (SUVs).
2. Background Art
A conventional non-tiltable gearshift unit often encroaches on the cab space and gets in the way when the driver wants to move from the driver's seat to the cab sleeping compartment which is normally located behind the drivers” seat. More generally, conventional gearshift units tend to make getting into and out of the driver's seat more difficult in all types of vehicle.
One solution to this problem that has long been known is to design the gearshift unit so that it can be tilted out of the way, thereby making it easier to get into and out of the driver's seat. Examples of such tiltable gearshift levers are described, for example, in Swedish Patent No. 511,030, U.S. Pat. Nos. 4,823,635 and 6,029,535, as well as the French Patent No. FR-2 752 779.
The aforementioned documents, however, all describe gearshift levers that are directly and mechanically coupled to the gearbox of the vehicle. However, more and more vehicles are nowadays being equipped with gearshift units of the so-called “shift-by-wire” type in which various positions of the gearshift lever are communicated to the gearbox by electronic signals without the existence of any mechanical clutch. Locating the gearshift unit in direct proximity to the driver's seat was also previously known in the case of gearshift units of the “shift-by-wire” type, it being possible to fold the entire gearshift unit down sideways, or to shift it rearwards in order to facilitate access to the sleeping compartment of the cab. An example of a gearshift unit of the “shift-by-wire” type in which the gearshift lever can be tilted in such a manner is given in the German Patent No. DE 19913835.
One problem with the aforementioned known tiltable gearshift levers and gearshift units is that of ensuring that the vehicle parking brake is applied when the gearshift lever or the gearshift unit is in the tilted position. This means that there is a risk of the vehicle accidentally starting to move uncontrolledly.